dr. Sebastian Koelling: Disassembling nano-structures atom by atom
|Wanneer:||wo 18-02-2015 13:30 - 14:30|
Controlling the assembly of materials and structures on the atomic scale promises considerable progress in a wide range of applications that can be utilized amongst others in the electronic, energy, chemical and health care industry. In order to understand and optimize the properties of these materials and structures, it is vital to have a grasp on the atomic arrangement in the fabricated specimens. Here we will demonstrate that we can use evaporation of single atoms induced by an electric field to disassemble nano-structures atom by atom. Analyzing the field evaporated atoms makes it possible to create a three-dimensional tomographic image including the approximate positions and the chemical identities of the atomic constituents in the disassembled structure. This technique, known as Atom Probe Tomography, enables us to identify and map atoms in nano-structures and nano-structured materials. The resulting maps allow us to characterize the nano-structure on a near atomic scale bringing us closer to the goal of imaging the full atomic arrangement of nano-structures in order to understand their properties.